Goals: NASA and the European Space Agency joined forces to send Ulysses to study the heliosphere - the region of space influenced by the Sun and its magnetic field - from a unique polar orbit. The spacecraft's 10 instruments on board measured the Sun's fields and particles, ultraviolet, X-rays and gamma rays.

Accomplishments: Ulysses was the first mission to survey the space environment above and below the poles of our Sun. The spacecraft used an unprecedented gravity assist maneuver at Jupiter to hurl itself out of the plane of the ecliptic and into its solar polar orbit.

During its 18-year mission, Ulysses made nearly three complete orbits of the Sun. The probe revealed for the first time the three-dimensional character of galactic cosmic radiation, energetic particles produced in solar storms and the solar wind. Not only has Ulysses allowed scientists to map constituents of the heliosphere in space, its longevity enabled them to observe the Sun over a longer period of time than ever before.

The spacecraft's six-year orbits over the Sun's poles allowed scientists to observe our star from an unprecedented angle during both calm and turbulent periods. Ulysses also made the first direct measurements of interstellar dust particles and interstellar helium atoms in the solar system and the discovery that the magnetic field leaving the Sun is balanced across latitudes.